Various arrangements of pins on shafts for mixing devices, e.g. for carbon black pelleters, have been proposed. Many of these pinned shafts have the pins arranged in comblike and/or disclike patterns. A comblike pattern is one wherein the pins extending radially from the shaft surface are arranged in a small number (e.g. four) of imaginary planes which are passed through the longitudinal axis of the shaft, and contain the longitudinal axis of the shaft. A disclike pattern is one wherein the radially extending pins are all arranged in a pattern of a small number (e.g. six) of circles, or, in other words, which radial extending pins lie in the same imaginary plane which is passed perpendicularly to the longitudinal axis of the shaft. These arrangements of the pins have disadvantages. Particularly, the comblike structure with even a very few combs causes surging of the drive mechanism for the pin shaft when operated in a horizontally arranged housing. The disc structure concentrates the pin action in a few areas with essentially no pin action between these locations along the axis or with changing intensities of the pin action.
Another arrangement of pins on a shaft has been proposed wherein the pins are arranged on a so-called defective helix having varying pitch. Whereas this arrangement achieves more uniform pin distribution, the pins are still not arranged in completely identical patterns so that the pin density varies slightly across the shaft. The distance between the pins and their next neighbors is not constant in this embodiment of a pinned shaft. Furthermore, the method to produce such a pinned shaft involves a demanding procedure.